Marine compound catunaregin inhibits angiogenesis through the modulation of phosphorylation of akt and eNOS in vivo and in vitro

Recent Advances of the Zebrafish Model in the Discovery of Marine Bioactive Molecules

Marine natural products are increasingly utilized in nutrition, cosmetics, and medicine, garnering significant attention from researchers globally. With the expansion of marine resource exploration in recent years, the demand for marine natural products has risen, necessitating rapid and cost-effective activity evaluations using model organisms. Zebrafish, a valuable vertebrate model, has become an efficient tool for screening and identifying safe, active molecules from marine natural products. This review, based on nearly 10 years of literature, summarizes the current status and progress of zebrafish models in evaluating marine natural product bioactivity. It also highlights their potential in exploring marine resources with health benefits, offering a reference for the future development and utilization of marine biological resources.

Chemical Constituents and Biological Activities of Bruguiera Genus and Its Endophytes: A Review

The genus Bruguiera, a member of the Rhizophoraceae family, is predominantly found in coastal areas as a mangrove plant, boasting a rich and diverse community of endophytes. This review systematically compiled approximately 496 compounds derived from both the Bruguiera genus and its associated endophytes, including 152 terpenoids, 17 steroids, 16 sulfides, 44 alkaloids and peptides, 66 quinones, 68 polyketides, 19 flavonoids, 38 phenylpropanoids, 54 aromatic compounds, and 22 other compounds. Among these, 201 compounds exhibited a spectrum of activities, including cytotoxicity, antimicrobial, antioxidant, anti-inflammatory, antiviral, antidiabetic, insecticidal and mosquito repellent, and enzyme inhibitory properties, etc. These findings provided promising lead compounds for drug discovery. Certain similar or identical compounds were found to be simultaneously present in both Bruguiera plants and their endophytes, and the phenomenon of their interaction relationship was discussed.

α-Amylase Inhibitory Activity of Catunaregam spinosa (Thunb.) Tirveng.: In Vitro and In Silico Studies

α-Amylase is an enzyme involved in the breaking down of large insoluble starch molecules into smaller soluble glucose molecules. Catunaregam spinosa (Thunb.) Tirveng. (syn. Randia dumetorum (Retz.) Lam., Family: Rubiaceace) has been used as traditional medicine for the treatment of gastrointestinal problems, skin diseases, and diabetes. In this context, we studied the in vitro α-amylase inhibiting properties of methanol extracts of leaves and bark of C. spinosa. The methanol extract of bark was further fractionated into hexane, dichloromethane and ethyl acetate, and water-soluble fractions, and their α-amylase inhibitory activity was evaluated. In silico molecular docking and ADMET analysis of several compounds previously reported from the bark of C. spinosa were also performed. The in vitro α-amylase inhibition activity assay of the dichloromethane fraction of extract of bark (IC₅₀: 77.17 ± 1.75 μg/mL) was more potent as compared to hexane and ethyl acetate fractions. The in silico molecular docking study showed that previously reported compounds from the stem bark such as balanophonin, catunaregin, β-sitosterol, and medioresinol were bounded well with the active catalytic residue of porcine pancreatic α-amylase indicating better inhibition. The ADMET analysis showed the possible drug-likeness and structure-activity relationship of selected compounds. These compounds should be studied further for their potential α-amylase inhibition in animal models.

Efficacy of marine biomolecules on angiogenesis by targeting hypoxia inducible factor/vascular endothelial growth factor signaling in zebrafish model

Marine resources are notably explored for their unique biomolecules that have been designed to be drug targets for their immense potential against various pathologies. These biomolecules are mostly secondary metabolites from different species that include sponges, tunicates, echinoderms, ascidians, algae, and marine symbionts. Among the various biological activities of the marine biomolecules, antiangiogenic property has gained much significance in alternate therapy for treatment against cancer. Hypoxia inducible factor (HIF) and vascular endothelial growth factor (VEGF) are the prime signaling pathways related to angiogenesis that are exclusively designated as markers for critical selection of novel inhibitors. This is mainly due to their importance in tumor induction and regulatory control over other interlinked pathways involved in cancer. Small molecular drug screening using the zebrafish model has been an advantage in cancer research in recent times. This review addresses the importance of marine biomolecules and their antiangiogenic efficacy by targeting HIF/VEGF pathways experimented in the zebrafish model in the last decade. Thus, it would provide more clear insights into the role of biomolecules in alternative cancer therapy.

Catunaregam spinosa (Thunb.) Tirveng: A Review of Traditional Uses, Phytochemistry, Pharmacological Activities, and Toxicological Aspects

Catunaregam spinosa (Thunb.) Tirveng. (Syn. Randia dumetorum (Retz.) Lam.), belonging to the Rubiaceae family, is distributed in south Asian countries. It is used as a traditional medicine to treat gastrointestinal and hepatic problems and as an anti-inflammatory and antimicrobial agent. The main aim of this review is to collect and analyze the available scientific information on traditional uses, phytochemistry, and pharmacological activities of C. spinosa. The scientific information related to C. spinosa was collected from various resources and databases such as SciFinder, Scopus, PubMed, and other databases. C. spinosa was found to be an important crude drug of the traditional medicinal systems such as Ayurveda. It was found to be used by the people of India as an alternative medicine, while the fruit of this plant was found to be used in dietary regimens as well. Active phytochemicals such as catunarosides, randianin, and several other saponins and triterpenoids possess various pharmacological activities such as anti-inflammatory, hepatoprotective, antibacterial, and immunomodulatory activities. Many studies have been performed to isolate the active compounds; however, there is a need for more activity-guided isolation studies. Various in vitro studies showed promising results but there are not many studies related to mechanism of actions using animal models. Hence, future studies on C. spinosa should focus on correlating the traditional uses with active phytoconstituents and modern pharmacological activities.

The influence of reduced graphene oxide on stem cells: a perspective in peripheral nerve regeneration

Graphene and its derivatives are fascinating materials for their extraordinary electrochemical and mechanical properties. In recent decades, many researchers explored their applications in tissue engineering and regenerative medicine. Reduced graphene oxide (rGO) possesses remarkable structural and functional resemblance to graphene, although some residual oxygen-containing groups and defects exist in the structure. Such structure holds great potential since the remnant-oxygenated groups can further be functionalized or modified. Moreover, oxygen-containing groups can improve the dispersion of rGO in organic or aqueous media. Therefore, it is preferable to utilize rGO in the production of composite materials. The rGO composite scaffolds provide favorable extracellular microenvironment and affect the cellular behavior of cultured cells in the peripheral nerve regeneration. On the one hand, rGO impacts on Schwann cells and neurons which are major components of peripheral nerves. On the other hand, rGO-incorporated composite scaffolds promote the neurogenic differentiation of several stem cells, including embryonic stem cells, mesenchymal stem cells, adipose-derived stem cells and neural stem cells. This review will briefly introduce the production and major properties of rGO, and its potential in modulating the cellular behaviors of specific stem cells. Finally, we present its emerging roles in the production of composite scaffolds for nerve tissue engineering.

Innovative Betulin Nanosuspension exhibits enhanced anticancer activity in a Triple Negative Breast Cancer Cell line and Zebrafish angiogenesis model

We present a nanosuspension of betulin, a BCS class II anticancer drug, particularly effective against resistant breast cancer. As anticancer efficacy of betulin is hampered by poor aqueous solubility, a nanosuspension with surface area was considered to enhance efficacy. An innovative approach wherein the betulin nanosuspension is generated instantaneously in situ, by adding a betulin preconcentrate (BeTPC) comprising drug and excipients, to aqueous medium, is successfully demonstrated. The optimal BeTPC when added to isotonic dextrose solution instantaneously generated an in situ nanosuspension (BeTNS-15) with high precipitation efficiency (92.7 ± 1.21%), average particle size (383.74 ± 7.24 nm) and good stability as per ICH guidelines. TEM revealed elongated particles while DSC and XRD indicated partial amorphization. Significantly higher cytotoxicity of BeTNS-15 (IC₅₀ 38.44 µg/ml) compared to betulin (BetS) (IC₅₀ 69.54 µg/ml) in the resistant triple negative human breast cancer cell line MDA-MB-231, was attributed to high intracellular uptake confirmed by HPLC and Imaging Flow cytometry (IFC). IFC confirmed superior anti-cancer efficacy of BeTNS-15 mediated by mitochondrial membrane disruption and inhibition of the G0/G1 phase. BeTNS-15 also exhibited significantly greater anti-angiogenic efficacy (p < 0.05) in the zebrafish model confirming superior efficacy. Simplicity of the innovative in situ approach coupled with superior efficacy proposes BeTNS as an innovative and highly promising anticancer formulation.

Antiangiogenic molecules from marine actinomycetes and the importance of using zebrafish model in cancer research

Blood vessel sprouting from pre-existing vessels or angiogenesis plays a significant role in tumour progression. Development of novel biomolecules from marine natural sources has a promising role in drug discovery specifically in the area of antiangiogenic chemotherapeutics. Symbiotic actinomycetes from marine origin proved to be potent and valuable sources of antiangiogenic compounds. Zebrafish represent a well-established model for small molecular screening and employed to study tumour angiogenesis over the last decade. Use of zebrafish has increased in the laboratory due to its various advantages like rapid embryo development, optically transparent embryos, large clutch size of embryos and most importantly high genetic conservation comparable to humans. Zebrafish also shares similar physiopathology of tumour angiogenesis with humans and with these advantages, zebrafish has become a popular model in the past decade to study on angiogenesis related disorders like diabetic retinopathy and cancer. This review focuses on the importance of antiangiogenic compounds from marine actinomycetes and utility of zebrafish in cancer angiogenesis research.

The role of inflammation, oxidative stress, angiogenesis, and apoptosis in the pathophysiology of endometriosis: Basic science and new insights based on gene expression

Endometriosis is a frequent and chronic illness in young women which could be defined by the existence of endometrial stroma and glands outside of the normal site of the lining of the uterus. It has painful symptoms. The advanced stage of endometriosis may lead to gynecological malignancies, such as ovarian cancer, and other complications, including infertility. However, its exact physiopathology is not well known. Recent studies have shown the possible roles of inflammation along with oxidative stress. Additionally, angiogenesis and apoptosis dysregulation contribute to endometriosis pathophysiology. Therapeutic strategies and continuing attempts, to conquer endometriosis should be done regarding molecular signaling pathways. Thus, the present review summarizes current studies and focuses on molecular mechanisms.

Tissue regeneration promotion effects of phenanthroimidazole derivatives through pro-inflammatory pathway activation

A chemotherapeutic drug exerts favorable antitumor activity and simultaneously exhibits expectable inhibition on wound healing process. Phenanthroimidazole derivatives possess potent anticancer activity. However, only a few studies focused on the discovery of its potential effects on promoting tissue regeneration. In this study, four novel phenanthroimidazole derivatives were synthesized and characterized, and they exhibited evident inhibition on different tumor cells; compound 3 is the most active one. Moreover, 3 can promote wound healing of zebrafish in a dose-dependent manner. Further study demonstrated that 3 promoted the recruitment of inflammatory cells, formation of angiogenesis, and generation of reactive oxygen species and also influenced the motor behavior of zebrafish. Results indicated that 3 can accelerate the occurrence of pro-inflammation, angiogenesis, oxidative stress, and innervation, which play key roles in the facilitation of wound healing. Therefore, 3 can act as a bifunctional drug in inhibiting tumor and promoting tissue regeneration.

The Impact of Human Papilloma Viruses, Matrix Metallo-Proteinases and HIV Protease Inhibitors on the Onset and Progression of Uterine Cervix Epithelial Tumors: A Review of Preclinical and Clinical Studies

Infection of uterine cervix epithelial cells by the Human Papilloma Viruses (HPV) is associated with the development of dysplastic/hyperplastic lesions, termed cervical intraepithelial neoplasia (CIN). CIN lesions may regress, persist or progress to invasive cervical carcinoma (CC), a leading cause of death worldwide. CIN is particularly frequent and aggressive in women infected by both HPV and the Human Immunodeficiency Virus (HIV), as compared to the general female population. In these individuals, however, therapeutic regimens employing HIV protease inhibitors (HIV-PI) have reduced CIN incidence and/or clinical progression, shedding light on the mechanism(s) of its development. This article reviews published work concerning: (i) the role of HPV proteins (including HPV-E5, E6 and E7) and of matrix-metalloproteinases (MMPs) in CIN evolution into invasive CC; and (ii) the effect of HIV-PI on events leading to CIN progression such as basement membrane and extracellular matrix invasion by HPV-positive CIN cells and the formation of new blood vessels. Results from the reviewed literature indicate that CIN clinical progression can be monitored by evaluating the expression of MMPs and HPV proteins and they suggest the use of HIV-PI or their derivatives for the block of CIN evolution into CC in both HIV-infected and uninfected women.

Ginsenoside Rg3 inhibits angiogenesis in a rat model of endometriosis through the VEGFR-2-mediated PI3K/Akt/mTOR signaling pathway

OBJECTIVE

This study aimed to investigate the link between the inhibitory effect of ginsenoside Rg3 on the ectopic endometrium growth and the VEGFR-2-mediated PI3K/Akt/mTOR signaling pathway, a mechanism known to inhibit angiogenesis and induce ectopic endometrial cell apoptosis.

MATERIALS AND METHODS

A model of endometriosis was established by allotransplantation in rats. The rats were randomly divided into 5 groups: the ginsenoside Rg3 low-dose group (group A,5mg/kgBW/d of ginsenoside Rg3), the ginsenoside Rg3 high-dose group (group B, 10mg/kgBW/d of ginsenoside Rg3), the gestrinone group (group C, 0.5mg/kgBW/d of gestrinone), the control group (groupD, 10ml/kg BW/d of 0.5%CMC-Na) and the ovariectomized group (group E, 10ml/kgBW/d of 0.5%CMC-Na). Rats were executed after 21 days of continuous administration. The ectopic endometrium volume was measured and the inhibitory rate was calculated. The levels of serum estradiol (E2) and progesterone (P) were detected by Electro-Chemiluminescence Immunoassay (ECLI). The protein expressionof VEGF, VEGFR-2, p-Akt, and p-mTOR inthe ectopic endometrium wastested by immunohistochemistry(IHC) and Western Blotting. The mRNA expression levels of VEGF, VEGFR-2, Akt, and mTOR were tested by Real-Time Polymerase Chain Reaction (PCR). The apoptosis rate of the ectopic endometrial cells was detected by Terminal Deoxynucleotidyl Transferase-mediated Digoxigenin-dUTP Nick-End Labeling Assay(TUNEL).

MAIN RESULTS

Tissue measurements revealed a dose-dependent inhibition effect of ginsenoside Rg3 on the growth of the ectopic endometrium in treated rats compared to controls. Immunohistochemical and Western Blotting assays confirmed that the expression of VEGF, p-Akt, and p-mTOR was down-regulated in ginsenoside Rg3 -treated lesions. Real-time PCR results also showed that the mRNA expression levels of VEGF, Akt, and mTOR in the ectopic endometrium were reduced.

CONCLUSIONS

The present study demonstrates, for the first time, that ginsenoside Rg3 suppresses angiogenesis in developing endometrial lesions. The ginsenoside Rg3 inhibitory effect on the growth of the ectopic endometrium in EMs rats might occur through the blocking of the VEGFR-2-mediated PI3K/Akt/mTOR signaling pathway, thus halting angiogenesis and promoting the apoptosis of ectopic endometrial cells.

Marine natural products

This review covers the literature published in 2014 for marine natural products (MNPs), with 1116 citations (753 for the period January to December 2014) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1378 in 456 papers for 2014), together with the relevant biological activities, source organisms and country of origin. Reviews, biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.

Concise asymmetric total synthesis of catunaregin

The asymmetric total synthesis of the optically pure catunaregin was accomplished in 7 steps from a known methyl ester using an asymmetric syn-selective aldol reaction and the successive ketalization of a furan diol derivative under acidic conditions.

Graphene Oxides Show Angiogenic Properties

Angiogenesis, a process resulting in the formation of new capillaries from the pre-existing vasculature plays vital role for the development of therapeutic approaches for cancer, atherosclerosis, wound healing, and cardiovascular diseases. In this report, the synthesis, characterization, and angiogenic properties of graphene oxide (GO) and reduced graphene oxide (rGO) have been demonstrated, observed through several in vitro and in vivo angiogenesis assays. The results here demonstrate that the intracellular formation of reactive oxygen species and reactive nitrogen species as well as activation of phospho-eNOS and phospho-Akt might be the plausible mechanisms for GO and rGO induced angiogenesis. The results altogether suggest the possibilities for the development of alternative angiogenic therapeutic approach for the treatment of cardiovascular related diseases where angiogenesis plays a significant role.

The promise of zebrafish as a chemical screening tool in cancer therapy

Cancer progression in zebrafish recapitulates many aspects of human cancer and as a result, zebrafish have been gaining popularity for their potential use in basic and translational cancer research. Human cancer can be modeled in zebrafish by induction using chemical mutagens, xenotransplantation or by genetic manipulation. Chemical screens based on zebrafish cancer models offer a rapid, powerful and inexpensive means of evaluating the potential of suppression or prevention on cancer. The identification of small molecules through such screens will serve as ideal entry points for novel chemical therapies for cancer treatment. This article outlines advances that have been made within the growing field of zebrafish cancer models and presents their advantages for chemical drug screening.

Widdrol, a sesquiterpene isolated from Juniperus chinensis, inhibits angiogenesis by targeting vascular endothelial growth factor receptor 2 signaling

Widdrol is an odorous compound derived from Juniperus chinensis that is widely used in traditional medicine to treat fever, inflammation and cancer. It was previously reported that widdrol has antitumor activity by apoptosis induction in cancer cells in vitro. However, its anti-angiogenic activity remains elusive. In the present study, we investigated the anti‑angiogenic activity of widdrol and the molecular mechanisms involved. Widdrol inhibited cell proliferation via G1 phase arrest induction in human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. Additionally, it was associated with a decreased expression of cyclin-dependent kinase 2 (CDK2) and an increased expression of p21, a CDK inhibitor. Widdrol significantly inhibited the cell migration and tube formation of HUVECs using an in vitro angiogenesis assay. The results showed that widdrol suppressed phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream proteins, such as AKT, focal adhesion kinase (FAK) and endothelial nitric oxide synthase (eNOS). Moreover, widdrol effectively reduced tumor growth and blood vessel formation in colon tumor xenograft mice. Collectively, these results suggested that widdrol may act as a potential anti-angiogenic agent by inhibiting vessel sprouting and growth, which may have implications for angioprevention.